Robustness of critical U(1) spin liquids and emergent symmetries in tensor networks
- URL: http://arxiv.org/abs/2008.04833v2
- Date: Tue, 28 May 2024 20:07:49 GMT
- Title: Robustness of critical U(1) spin liquids and emergent symmetries in tensor networks
- Authors: Henrik Dreyer, Laurens Vanderstraeten, Ji-Yao Chen, Ruben Verresen, Norbert Schuch,
- Abstract summary: We study the response of critical Resonating Valence Bond (RVB) spin liquids to doping with longer-range singlets.
We find that in the RVB, doping constitutes a relevant perturbation which immediately opens up a gap.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We study the response of critical Resonating Valence Bond (RVB) spin liquids to doping with longer-range singlets, and more generally of U(1)-symmetric tensor networks to non-symmetric perturbations. Using a field theory description, we find that in the RVB, doping constitutes a relevant perturbation which immediately opens up a gap, contrary to previous observations. Our analysis predicts a very large correlation length even at significant doping, which we verify using high-accuracy numerical simulations. This emphasizes the need for careful analysis, but also justifies the use of such states as a variational ansatz for critical systems. Finally, we give an example of a PEPS where non-symmetric perturbations do not open up a gap and the U(1) symmetry re-emerges.
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